function [x,y,s] = mask_mn(a,idx,orient,vals)

x = cell(2,1);
y = cell(2,1);
s = cell(2,1);

x{1} = [-1 -1 1 1 -1];
y{1} = [-1 1 1 -1 -1];
s{1} = 'k';

x{2} = [-0.35 -0.35 0 0.35 0.35];
y{2} = [-0.35 0.35 0.05 0.35 -0.35];
s{2} = 'b';
